As an example of a medical device, a soft contact lens (a soft ophthalmic lens) is exemplified. In a commercially available soft contact lens, a hydrogel material having a water content of about 25% to about 80% is usually used. Among them, a medical device and the like in which a silicone hydrogel having high oxygen permeability is used as a base material and a surface of the base material is modified in a hydrophilic property by coating the base material with two or more polymer materials layer by layer and stacking is disclosed (Patent Literatures 1 and 2).
A method of alternately coating a base material with polymer materials having two opposite charges layer by layer, which is disclosed in Patent Literatures 1 and 2, is called an LbL method. The layers of each material are considered to be bonded to the other layers made of a different material in a noncovalent bond manner. However, the LbL coating has been carried out with many layers such as about 4 layers to about 20 layers, and therefore, a production process may become longer and a production cost may increase. In the methods of the patent literatures described above, although the hydrophilic property of the surface of the base material can be improved, antifouling properties, particularly lipid adhesion resistance, are not improved.